Astronomy and Astrophysics – Astronomy
Scientific paper
Mar 1995
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995aj....109.1320k&link_type=abstract
Astronomical Journal (ISSN 0004-6256), vol. 109, no. 3, p. 1320-1326
Astronomy and Astrophysics
Astronomy
19
Infrared Spectra, Ion Density (Concentration), Late Stars, Planetary Nebulae, Stellar Evolution, Stellar Temperature, Visible Spectrum, Absorption Spectra, Abundance, Emission Spectra, Spectrum Analysis, Stellar Spectrophotometry, Vibrational Spectra
Scientific paper
We present spectra taken between lambda = 0.9 - 1.3 micrometers for a sample of evolved stars ranging from Mira variable stars to planetary nebulae. An evolution can be seen from the absorption spectra of the late-type stars to the emission line spectra of the planetary nebulae. We compare emission line strengths for objects ranging from Teff = 30 000 to 200 000 K, and we use infrared and visible line ratios to determine densities and temperatures in the emission line regions. We examine the four factors that are most important to determining relative ion strengths-stellar temperature, evolutionary status, excitation mechanism, and clumpiness. It is found that clumps appear to be common, and that shocks are very important to the excitation and shaping of planetary nebulae, We also find that the strength of the low ionization and molecular emission lines decreases with age, and we use a filling factor analysis to show that this evolution is caused by a decrease in the amount of low ionization material close to the star.
Kelly Douglas M.
Latter William B.
No associations
LandOfFree
Spectroscopy of evolved stars in the near infrared: Explorations beyond the AGB does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Spectroscopy of evolved stars in the near infrared: Explorations beyond the AGB, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spectroscopy of evolved stars in the near infrared: Explorations beyond the AGB will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-883981